Chbis



' a thin coating.

UNITED TATES PATENT OFFICE.

CHRIS. BAKER, OF INDIANAPOLIS, INDIANA, ASSIGNOR OF ONE-HALF TO BENJAMIN O. HAUGH, OF SAME PLACE.

PREPARATION FOR AND PROCESS OF TREATING THE FACES 0F SAND MOLDS.

.QJECIPICATION forming part of Letters Patent No. 308,821, dated December 2, 1884.

Application tiled April 3, 1884. (No specimens I To aZZ whom it may concern:

Be it known that I, OHRIs. BAKER, of the city of Indianapolis, county of Marion, and State of Indiana, have invented certain new and useful Improvements in Preparations for and Processes of Treating the Faces of Sand Molds, of which the following is a specification.

My invention consists in a preparation for and process of treating the face of sand molds for making metal castings.

The preparation consists of resin, plumba go, and gasoline, or equivalents of said sub stances, Which are used in substantially the following proportions: resin, one-half pound; plumbago, one pound, and gasoline one quart.

Theprocess oftreating molds with this preparation is as follows: The mold is first prepared in the usual form. The resin and plumbago are then powdered and mixed and dusted evenly over the face ofthe mold, so as to form The gasoline is then poured on and lighted and allowed to burn as long as it will. This dries the face of the mold and also forms a crust, to which the iron in casting will not adhere, but which is sufliciently porous to allow all gases to escape, and thus prevents bubbles from forming in the iron, and also prevents it from scabbing. If desired, all the substances may be mixed to gether before being applied to the mold; but

I prefer the method above described, as by that method greater evenness and uniformity can be secured.

The resin and gasoline alone are capable of being used as a drier, and so far accomplish my purpose. The plumbago is added for the purpose of causing the sand to scale 'cleanly off the casting, and thus leave said casting smooth and free from scabs.

Having thus fully described my said invention, what I claim as new, and desire to secure by Letters Patent, is

1. The process of drying sand molds which consists in applying resinous inflammable substances to the face of the mold and then burning the same, substantially as set forth.

2. The process of treating sand molds which consists in applying pulverized plumbago and resin and an inflammable liquid, and setting said inflammable liquid on fire, substantially as described, and for the purposes specified.

3. A preparation for treating molds, consisting of resin, plumbago, and an inflammable liquid, substantially as set forth.

In witness whereof I have hereunto set my hand and seal, at Indianapolis, Indiana, this 18th day of March, 1884.

CHRIS. BAKER. [L. s.]

Witnesses:

E. W. BRADFORD, CHAS. L. THURBER. 

